Outcome following traumatic brain injury in the elderly: a critical review

Background: The elderly are at risk for traumatic brain injury (TBI), but t heir outcome following these injuries remains unclear. Objective: This paper critically reviews research done to date on cognitive and functional outcome following TBI in the elderly. Methods: MEDLINE and PSYCHLIT databases going back to 1965 were searched. Results: Studies suggest that TBI results in adverse cognitive and function al outcomes in the elderly. There is uncertainty as to whether TBI is a sig nificant risk factor for Alzheimer's disease (AD). Methodological problems in these studies include selection bias, small samples, retrospective analy ses, and, particularly, the failure to address the role of pre-morbid funct ioning. These problems limit the strength of the outcome studies, and may a ccount for the equivocal findings on AD risk. Conclusions: It is premature to conclude from the published research to dat e that the elderly have a uniformly poor outcome following TBI. Directions for further research are suggested.